Thread: Octane rating or ethanol. Which is more

important? My dealer has told me to use 89 octane gas in my mower and handhelds. On the other hand, I can get ethanol free gas in 87 octane. Would the ethanol free/lower octane be better to run? Thanks

That being said, I have not experienced but one problem that I could even relate to ethanol...I think sometimes its used as a thing to blame for crap equipment and poor mechanic work...I'm not saying this is the case all of the time.Posted via Mobile Device

ethanol can and has been proven to be harder on seals and stuff in fuel systems of vehicles. it can eat certain rubbers pretty quickly. newer ones are designed with this in mind but older engines can have problems related to it. it's pretty standard around here to have at least 10% ethanol. the other issue i have with ethanol is there is less energy per gallon than straight gasoline, so you need more ethanol to make the same power. this translates to lower fuel mileage. granted at 10% its not a huge difference but it's still there all the same.

ethanol can and has been proven to be harder on seals and stuff in fuel systems of vehicles. it can eat certain rubbers pretty quickly. newer ones are designed with this in mind but older engines can have problems related to it. it's pretty standard around here to have at least 10% ethanol. the other issue i have with ethanol is there is less energy per gallon than straight gasoline, so you need more ethanol to make the same power. this translates to lower fuel mileage. granted at 10% its not a huge difference but it's still there all the same.

You've opened a can of worms now! I've said ethanol produces less energy on here before and was ridiculed.Posted via Mobile Device

Ethanol has less carbon per pound versus petroleum because of the oxygen in its molecule. The lower percentage of carbon is why there are fewer BTUs, therefore less energy released when it is burned or used in an engine. That oxygen in its molecule is what contributes to its corrosive properties above and beyond what is caused by its tendency to absorb water. In terms of fuel value: ethanol<gasoline<biodiesel<diesel.